Food Poisoning
What is it?
Food poisoning refers to illness brought on by ingesting foods contaminated with living micro-organisms, toxins produced by microorganisms, poisonous chemicals, or poisonous fish, shellfish, or plants (such as mushrooms). The digestive tract is most commonly affected. However, botulism, a life-threatening form of food poisoning, primarily affects the nervous system and may cause respiratory failure (see Botulism for more information).
Food poisoning may result from improper storage and handling of food, such as inadequate refrigeration or touching food with soiled hands or machinery. Symptoms generally develop within one to 48 hours after eating. Some types of food poisoning (notably cholera and shigellosis) may take from three to five days to produce symptoms.
Food poisoning is suspected when sudden, acute gastrointestinal symptoms arise. It is difficult to prove that food poisoning is the cause of illness unless several people develop symptoms after sharing a meal or after eating in the same restaurant. The illness often subsides spontaneously after one to five days; however, severe or persistent symptoms require treatment and sometimes hospitalization.
What Causes It?
- Preformed bacterial toxins produced by overgrowth of certain bacteria before food is eaten.
- Contamination with live microorganisms that proliferate in the intestine and may invade tissues or produce toxins.
- Poisonous metals.
- Poisons in fish, shellfish, and plants (mushrooms).
Prevention
- Wash your hands thoroughly with warm water and soap before preparing food.
- Make sure food is handled, cleaned, cooked, and refrigerated properly.
- Don't buy or use food in cans that are rusty, bulging, dented, or leaking.
- Avoid tasting food to check for contamination.
- Don't eat mushrooms you have picked.
- Don't consume unpasteurized dairy products.
- Throw away any questionable leftovers.
Diagnosis
- Vomit, feces, or blood may be cultured or tested.
- If available, samples of suspected foods are examined for contaminants.
How to Treat It
- Diarrhea may help rid the body of bacteria and toxins. For that reason, check with your doctor before taking anti-diarrheal medications.
- Drink plenty of fluids to prevent dehydration from diarrhea.
- A drink containing electrolytes and sugar may be needed to replace minerals lost with severe diarrhea.
- Intravenous fluids may be needed to treat severe dehydration.
- Medication to prevent vomiting (antiemetics) may be prescribed in severe cases, although vomiting may help rid the body of toxins.
- Antibiotics may be prescribed in some cases, if certain infectious agents are involved.
When to Call a Doctor
- The elderly, young children, and anyone with a weakened immune system (such as those diagnosed with AIDS or undergoing treatment for cancer) should be taken to a doctor immediately if they develop even mild symptoms of food poisoning. These people are at greater risk of life-threatening complications.
- Call a doctor if you develop any of the following: sudden, severe or bloody diarrhea; a fever over 102 degrees; severe abdominal pain.
- Call a doctor if food poisoning symptoms do not subside within a week.
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Copyright © 2008 Medletter Associates, LLC
Content excerpted from Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference.